Coreopsis plant named ‘Citrine’

ABSTRACT

A new and distinct  Coreopsis  plant named ‘Citrine’ characterized by daisy-type flowers that grow to 4 cm in diameter, flowers that are clear yellow, grass green foliage on short stems, flowers all summer, a dense, compact, mounding habit, and excellent vigor.

Botanical denomination: Coreopsis spp.

Variety designation: ‘Citrine’.

Parentage: Coreopsis ‘Rum Punch’ (U.S. Plant Pat. No. 18,889)×C.pubescens.

BACKGROUND OF THE INVENTION

The present invention relates to a new and distinct Coreopsis and giventhe cultivar name ‘Citrine’. Coreopsis is in the family Asteraceae. Thisnew cultivar originated from a controlled cross of Coreopsis ‘Rum Punch’(U.S. Plant Pat. No. 18,889) as the seed parent and Coreopsis pubescens,an unpatented plant, as the pollen parent. The breeding program is toproduce hardy dwarf cultivars.

Compared to the seed parent, Coreopsis ‘Rum Punch’, the new cultivar hasflowers that yellow rather than orangey-rose and the habit is smallerand tighter. Compared to the pollen parent, Coreopsis pubescens, the newcultivar has flowers that are a lighter yellow and leaves that are muchnarrower. The habit is smaller and tighter.

Compared to Coreopsis grandiflora ‘Presto’, an unpatented plant, the newvariety has single flowers of clear yellow rather than a golden doubles.

SUMMARY OF THE INVENTION

The following traits have been repeatedly observed and are determined tobe the unique characteristics of the new variety. These characteristicsin combination distinguish Coreopsis ‘Citrine’ as a new and distinctcultivar:

-   -   1. daisy-type flowers that grow to 4 cm in diameter,    -   2. flowers that are clear yellow,    -   3. grass green foliage on short stems,    -   4. flowering for the whole summer,    -   5. a dense, compact, mounding habit, and    -   6. excellent vigor.

This new cultivar has been reproduced only by asexual propagation(cuttings and tissue culture). Each of the progeny exhibits identicalcharacteristics to the original plant. Asexual propagation by cuttingsand tissue culture using standard micropropagation techniques withterminal and lateral shoots, as done in Canby, Oreg., shows that theforegoing characteristics and distinctions come true to form and areestablished and transmitted through succeeding propagations. The presentinvention has not been evaluated under all possible environmentalconditions. The phenotype may vary with variations in environmentwithout a change in the genotype of the plant.

BRIEF DESCRIPTION OF THE PHOTOGRAPH

The photograph shows one-year-old Coreopsis ‘Citrine’ growing in theground in the trial field in August in Canby, Oreg.

DETAILED PLANT DESCRIPTION

The following is a detailed description of the new Coreopsis cultivarbased on observations of four-month-old specimens growing in a four inchpots in a warm greenhouse in Canby, Oreg. Canby is Zone 8 on the USDAHardiness map. Temperatures range from a high of 95 degrees F. in Augustto 32 degrees F. in January. Normal rainfall in Canby is 42.8 inches peryear. The color descriptions are all based on The Royal HorticulturalSociety Colour Chart, 5^(th) edition.

-   Plant:    -   -   Type.—Herbaceous perennial.        -   Hardiness.—USDA Zones 7 to 9.        -   Size.—22 cm wide and 23 cm tall to top of inflorescences.        -   Form.—Mound.        -   Vigor.—Excellent.        -   Roots.—Fibrous, stems root easily from stem cuttings.-   Stem:    -   -   Type.—Ascending.        -   Size.—13 cm tall to where branches for flowering and 4 mm            wide.        -   Number of stems from the crown.—2 to 4.        -   Internode length.—1 to 3 cm.        -   Surface.—Pubescent.        -   Color.—Green 137A.-   Leaf:    -   -   Type.—Simple.        -   Shape.—Ovate, 1 to 5 pinnate, pinnae linear lanceolate.        -   Arrangement.—Opposite.        -   Size.—Grows to 14 cm long and 5.5 mm wide.        -   Apex.—Acute.        -   Margins.—Entire.        -   Petiole.—Grows to 5.5 cm long 1 to 2 mm wide, pubescent,            Green 137A.        -   Surface texture.—Pubescent on top and bottom sides.        -   Venation.—Pinnate.        -   Color.—Topside Green N137A, bottom side Green N137B.-   Inflorescence:    -   -   Type.—Long stalked terminal heads of daisy type            inflorescences.        -   Peduncle.—Grows to 6 cm long, 1 mm wide, glabrous, Green            137A.        -   Size.—Grows to 4.2 cm wide and 9 mm deep.        -   Immature.—Globular, 7 mm wide and 6 mm deep, Yellow Green            152A on the sides and Yellow Green 153C on top, glabrous.        -   Receptacle.—Disc shaped, 3 mm wide and 1.5 mm deep, Green            148B.        -   Phyllaries.—In 2 series; first series closet to ray florets            5 mm deep and 15 mm wide, 8 in number, each 5.5 mm long and            3.5 mm wide, ovate, margin entire, tip acute, glabrous on            both sides, both sides Yellow Green 152A; lower series in an            area 3 mm deep and 8 mm wide, 5 in number, 3 mm long and 1.5            mm wide, each ovate, margin entire, tip acute, both sides            glabrous and Yellow Green 146A.        -   Lastingness.—Each inflorescence lasts about a week on the            plant.-   Florets:    -   -   Type.—Composite.        -   Ray florets.—8 in number with no pistil or stamen, grows to            18 mm long, 7 mm wide, obovate, with the tip three-lobed            with lobe tips obtuse and the central lobe the longest,            sometimes notched, margins entire, glabrous on both sides;            topside Yellow 9A, bottom side Yellow 9B.        -   Disc.—Conic, deeper with maturity, 8 mm wide and becoming 3            mm deep with maturity, after opening Yellow Orange 21A.        -   Disc florets.—Tubular, with stamen and pistil, about 110 in            number, 5 mm long and 1 mm wide, tubular; corolla 2.5 mm            long, Yellow 13B; pistil 1, 5 mm long, ovary 1 mm long,            Green Yellow 1C, style 5 mm long, with extruding, 2-branched            stigma, stigma and style Yellow 13B; stamen 5, anthers 1.2            mm long, Greyed Brown N199 B, no pollen, male sterile.        -   Bloom period.—June through September in Canby, Oreg.        -   Fragrance.—Light, Chrysanthemum-like.        -   Seed.—None seen.        -   Fertility.—Sterile.-   Disease and pests: Coreopsis are susceptible to mildew and fungal    spots. No resistance is known for this variety.

1. A new and distinct Coreopsis plant as herein illustrated anddescribed.